Screw forming die for plum-blossom-shaped porous grain

Abstract

The invention discloses a screw forming mold for a plum-blossom-shaped porous grain. The screw forming mold comprises a rear cone, a front cone and a mold front section which form a mold cavity, a copper sleeve fixed to the outlet end of the mold cavity, and a combined mold needle assembly arranged in the mold cavity. The combined mold needle assembly comprises an inner mold needle assembly and an outer mold needle assembly; the outer die needle assembly is composed of a rear needle frame and outer die needles, the rear needle frame is composed of a large annular frame and a small annular frame which are coaxial, the large annular frame is connected with the small annular frame through a rib plate, and the small annular frame is connected with the outer die needles through a conical frame; the inner mold needle assembly and the outer mold needle assembly are arranged front and back, and inner mold needles of the inner mold needle assembly are inserted into all outer mold needles of the outer mold needle assembly, so that the inner wall of the copper sleeve, the inner mold needles and all the outer mold needles form a pressing molded surface matched with the plum-blossom-shaped porous grain. By means of the forming die, trial-manufacture of the large-size equal-surface-combustion plum-blossom-shaped porous grain is achieved.

Description

Technical Field

[0001] The invention relates to a screw-pressing forming die for a plum blossom-shaped porous medicine column, and belongs to the field of die design. Background Art

[0002] For a long time, the shape structure of screw-pressed propellants in China has been mainly simple tubular, cylindrical, and inner star hole loading, and the screw-pressed integrated molding of large-sized equal-surface combustion porous grain columns has not been achieved. The main reasons are that the temperature field, pressure field, velocity field, etc. in the screw-pressed molding process of complex charge are unclear, the mechanism of the coupling of material characteristics, mold structure, and process parameters on the molding quality is unclear, and the equipment is limited. In order to achieve the effect of large combustion surface, under the existing conditions, a compromise is adopted to form a brush-type charge structure by bonding and assembling multiple tubular charges in the later stage. Because the brush-type charge structure is assembled by bonding multiple charge columns, it requires more post-processing processes, including secondary heating, truncation, measurement, matching, and solidification operations, as well as moving and transporting between multiple processes. In particular, the solidification process is mostly manual, time-consuming, and requires high operating requirements for employees. The stability and consistency of the operation are directly related to the stability and consistency of the charge performance. In addition, the solidification process also has a high safety risk, and serious safety accidents caused by the friction of the plugging have occurred. Mold structure is one of the key factors affecting the molding of propellant grains, especially for complex charge types. The mold structure is complex, such as flow channel compression ratio, mold hole arrangement, molding section aspect ratio, needle arrangement, diversion angle, etc., which will affect the flow field characteristics of the molding process, the pressure, temperature, shear rate, streamline distribution characteristics and extrusion expansion behavior in the die head. Unreasonable mold structure design will directly lead to the extruded grain not being formed, loose molding, uneven molding, too high torque to extrude, or screw press "slipping" and other phenomena. At present, although the brush-type charge formed by screw pressing and the large-size equal-surface combustion porous charge formed by casting can meet the performance requirements of weapons and equipment at this stage, they are limited by their own process and structural deficiencies. However, they cannot meet the pressing of plum blossom-shaped porous charge. The cross-sectional diagram of the charge is shown in the figure. Figure 5 shown. Summary of the invention

[0003] The purpose of the present invention is to solve the trial production of large-sized equal-surface combustion plum blossom-shaped porous powder columns, and to provide a spiral pressing molding die for plum blossom-shaped porous powder columns.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] The spiral pressing mold for a plum blossom-shaped porous drug column of the present invention comprises a rear cone, a front cone and a front section of the mold constituting a mold cavity, and a copper sleeve fixed at the outlet end of the mold cavity; it is characterized in that it also comprises a combined mold pin assembly arranged in the mold cavity;

[0006] The combined mold pin assembly comprises an inner mold pin assembly and an outer mold pin assembly;

[0007] The inner mold needle assembly is composed of a front needle frame and an inner mold needle fixed to the middle of the front needle frame through a rib plate;

[0008] The outer mold needle assembly is composed of a rear needle frame and an outer mold needle, the rear needle frame is composed of two coaxial annular frames, one large and one small, the large annular frame is connected to the small annular frame through a rib plate, and the small annular frame is connected to each outer mold needle through a conical frame;

[0009] The inner mold needle assembly and the outer mold needle assembly are arranged front and back, and the inner mold needle of the inner mold needle assembly is inserted into the inside of each outer mold needle of the outer mold needle assembly, so that the inner wall of the copper sleeve and the inner mold needle and each outer mold needle form a pressing surface matching the plum blossom-shaped porous medicine column.

[0010] The outer walls of the front needle frame and the rear needle frame are connected to the inner wall of the mold cavity through needle frame positioning keys, so that the combined mold needle assembly and the mold cavity maintain circumferential positioning.

[0011] The outer wall of the copper sleeve and the inner wall of the front section of the mold are connected through a copper sleeve positioning key, so that the outer wall of the copper sleeve and the front section of the mold maintain circumferential positioning.

[0012] Beneficial Effects

[0013] The molding die of the present invention realizes the trial production of large-sized equal-surface burning plum blossom-shaped porous grains, and the test pieces are well formed and the sizes meet the requirements, which can provide a reference for subsequent large-sized equal-surface burning special-shaped grains. Since the needle holder is reasonably designed, the screw pressure resistance is moderate, the flowability of the grain is good, the process temperature can be controlled according to the normal compression and stretching process of the propellant, and the load is within the normal range. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the screw forming mold of the present invention;

[0015] Figure 2 It is a structural schematic diagram of a combined mold pin assembly in a screw forming mold of the present invention;

[0016] Figure 3 It is a structural schematic diagram of the inner mold pin assembly in the screw forming mold of the present invention;

[0017] Figure 4 It is a structural schematic diagram of the outer mold pin assembly in the screw forming mold of the present invention;

[0018] Figure 5 It is a cross-sectional view of a plum blossom-shaped porous drug column;

[0019] In the figure, 1-rear cone, 2-combined mold needle assembly, 21-inner mold needle assembly, 211-front needle holder, 212-inner mold needle, 22-outer mold needle assembly, 221-rear needle holder, 222-outer mold needle, 3-front cone, 4-mold front section, 5-copper sleeve, 6-needle holder positioning key, 7-copper sleeve positioning key. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Example

[0022] like Figure 1 As shown, a spiral pressing mold for a plum blossom-shaped porous drug column of the present invention comprises a rear cone 1, a front cone 3 and a front section 4 of the mold constituting a mold cavity, a copper sleeve 5 fixed at the outlet end of the mold cavity, and a combined mold pin assembly 2 arranged in the mold cavity;

[0023] like Figure 2 As shown, the combined mold pin assembly 2 includes an inner mold pin assembly 21 and an outer mold pin assembly 22;

[0024] like Figure 3 As shown, the inner mold needle assembly 21 is composed of a front needle frame 211 and an inner mold needle 212 fixed to the middle of the front needle frame through a rib plate;

[0025] like Figure 4 As shown, the outer mold needle assembly 22 is composed of a rear needle frame 221 and an outer mold needle 222. The rear needle frame 221 is composed of two coaxial annular frames, one large and one small. The large annular frame is connected to the small annular frame through a rib plate, and the small annular frame is connected to each outer mold needle 222 through a conical frame.

[0026] The inner mold needle assembly 21 and the outer mold needle assembly 22 are arranged front and back, and the inner mold needle 212 of the inner mold needle assembly 21 is inserted into the inner part of each outer mold needle 222 of the outer mold needle assembly 22, so that the inner wall of the copper sleeve 5 and the inner mold needle 212 and each outer mold needle 222 form a pressing surface matching the plum blossom-shaped porous medicine column.

[0027] The outer walls of the front needle frame 211 and the rear needle frame 221 are connected to the inner wall of the mold cavity via a needle frame positioning key 6, so that the combined mold needle assembly 2 and the mold cavity maintain circumferential positioning.

[0028] The outer wall of the copper sleeve 5 is connected to the inner wall of the front section 4 of the mold via a copper sleeve positioning key 7, so that the outer wall of the copper sleeve 5 and the front section 4 of the mold maintain circumferential positioning.

Claims

1. A spiral pressing mold for a plum blossom-shaped porous drug column, comprising a rear cone, a front cone and a front section of the mold constituting a mold cavity, and a copper sleeve fixed at the outlet end of the mold cavity; characterized in that: Also included is a combined mold pin assembly disposed in the mold cavity; The combined mold pin assembly comprises an inner mold pin assembly and an outer mold pin assembly; The inner mold needle assembly is composed of a front needle frame and an inner mold needle fixed to the middle of the front needle frame through a rib plate; The outer mold needle assembly is composed of a rear needle frame and an outer mold needle, the rear needle frame is composed of two coaxial annular frames, one large and one small, the large annular frame is connected to the small annular frame through a rib plate, and the small annular frame is connected to each outer mold needle through a conical frame; The inner mold needle assembly and the outer mold needle assembly are arranged front and back, and the inner mold needle of the inner mold needle assembly is inserted into the inside of each outer mold needle of the outer mold needle assembly, so that the inner wall of the copper sleeve and the inner mold needle and each outer mold needle form a pressing surface matching the plum blossom-shaped porous medicine column.

2. A screw pressing mold for a plum blossom-shaped porous drug column as claimed in claim 1, characterized in that: The outer walls of the front needle frame and the rear needle frame are connected to the inner wall of the mold cavity through needle frame positioning keys, so that the combined mold needle assembly and the mold cavity maintain circumferential positioning.

3. A screw pressing mold for a plum blossom-shaped porous drug column as claimed in claim 1 or 2, characterized in that: The outer wall of the copper sleeve and the inner wall of the front section of the mold are connected through a copper sleeve positioning key, so that the outer wall of the copper sleeve and the front section of the mold maintain circumferential positioning.

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